Devices such as firewalls are sometimes used to prevent users from accessing resources to which they are not authorized. As an example, members of the public may be entitled to access content served by a web server, but not authorized to access other services available on the server such as administrative tools. In another example, employees of a company may be entitled to access certain websites or certain class of websites while other websites or other classes of websites may be prohibited for all employees. Firewalls and other security devices typically enforce policies against network transmissions based on a set of rules.
To implement effective security policy enforcement, a firewall needs to be capable of processing incoming data packets at the packet data rate of the protected network so that network traffic can be effectively examined as the traffic is being communicated. Furthermore, as firewalls or security devices are deployed in enterprise or data center applications, the firewalls often need to be scaled up to handle increased network traffic.